<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <script type="text/javascript" src="index.js" defer></script>
    <link type="text/css" rel="stylesheet" href="index.css" />
    <title>Document</title>
</head>

<body>
    <div></div>
    <input id="btn" type="button" value="test">

    <input id="button" type="button" value="测试">
</body>

</html>